A. Field of the Invention
This relates to the construction of large concrete structures and specifically enabling a worker to place a curve on the outside edge of the concrete slab such as a sidewalk while also producing a keyway for the wall at the same time.
B. Prior Art
There are many other prior art references to keyway making devices. A representative example of this type of device is found at Gauuan, U.S. Pat. No. 5,160,748. This reference makes a keyway in the center of the device and smoothes the concrete on the respective sides of the keyway. It does not produce a curved edge on the concrete slab.
The device in this case produces a keyway in the slab while at the same time produces a curved edge on the edge of the slab.